This cocktail was introduced by the British in India. Tonic water contains quinine, which was used to prevent malaria. Because the tonic water consumed to prevent malaria in the 19th century was extremely bitter, gin was added to make it more palatable. Although there is less medical use today for the consumption of tonic water, the gin and tonic remains a popular drink. Tonic water available today contains less quinine and is consequently less bitter (usually sweetened). Because of this connection to warmer climates and its refreshing nature, this cocktail is more popular during the warmer months.Lore has it that the sheer enormity of the the quantity of limes (for the prevention of Scurvy) and quinine (for the aforementioned prevention of malaria), was so unpalatable that the only way to get the members of the British Army to consume the prescribed amount was with the addition of gin.
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